Spring-tension means for brush-holders



APPUCATION HLED SEPT. 17, 1920.

Patentedlune 14, 1921.

, INVENTOR John 5. De n MBY ATTCIDRNEY entree s ares FTENT ELECTRIC & MAN'Ulih-CTU TY. COR-PUEi YLV SPBING1-TENSION Z IEAN'S FOE BldUSEI-HOLDERS.

Application filed SG tC111he;.

To all whom it may concern Be it known that l, Jenn S. Dr W a zen of the United tit-(dos 211. ltdgewood Park, in the cot gheny and Eitate of Pennsylvania. have in vented a new and useful improvement in Spring-Tension Means for Brush olders, of which the following is a specification.

My invention relates to bruslrhelders and it has particular relation to soring tension devices therefor.

Heretoiore, great diiiiculty has been encountered in obtaining the necessary degree of rotary ustment of the stud shaft upon which the brush. spring is mounted.

it has been customary to rotatabiy mount the stud shaft in the brushhold r tame and to maintain it therein without displ ment by means of cotter pins which extend through the bearing portion oi. the brushholder and the shaft. In order to obtain a variety of rotary adjustments of the shaft, it has been customary to provide both the bearing elements and the shaft with a plurality of intersecting radial apertures, dil

ferent ones of which were brought into alinement according to the degree of tension desired.

It has, however, been observed that by reason of the relatively small diameter of the shaft only acomparatively tew apertures may be provided in the same plane without materially weakening the shaft.

One of the objects of my invention is to provide a device of the character described wherein a relatively large number of ad justments may be readily obtained without materially weakening the spring shaft.

In the accompanying drawings:

Figure 1 is a side elevational view of a brush-holder constructed in accordance with my invention.

Fig. 2 is a plan view of a brush-holder frame with the brushes and spring removed. therefrom.

Fig. 3 is a view in side elevation of a brush spring shaft, illustrating; the staggored position of the adjusting apertures.

Fig. 4: is an end view of the shaft illustrated in Fig. 3.

Referring to the drawings:

A brush-holder embodying my invention is illustrated as comprising an integral frame member 1. of preferred construetion or material. The frame 1 is provided.

Specification of Letters Patent.

Patented June 1%21.

1?, 192%}. Serial No. erases.

at the forward end thereof, vertically with a disposed rectangular aperture 2 or box Within which a carbon slidabl mounted for vertical movement. A olurality of outwardly projecting lugs l, provided with apertures 5, are termed the other end of the frame 1, preferably adjacent the corners thereof. iertieally extending insulated posts 6 are secured in the apertures 5 by means of pins '5. The upper ends of the posts 6 are rigidly clamped to the main casing or. frame 8 of the machine by means of (Jo-acting jaw members 9 and a bolt 10. The posts 6 are provided with insulators l1 adapted to increase the ere-spans distance tween the brushdiolder and casino" 8 of the machine. J

The frame 1 is termed with a substantially rectangular opening 12 having bottom 13 and side wallsl i the latter of which are provided with inwardly extending bosses or bearing members 15. The. bearing members 15 are provided with a plurality oi in tersecting apertures 16 extending radially therethrough, and which are shown as being disposed at 30 intervals apart. A stud shaft 17 is mounted for rotary adjustment in the bearings 15 and is also provided at each end thereof with a plurality of similar apertures i8 staggered with respect to each other and adapted to alterinitely register with the apertures 16 and the bearings The shaft 17 is further provided in one end thereof with a slot 19 adapted to receive 'a screw driver or other suitable tool by means of which the shaft 17 may be retated to obtain the necessary adjustments.

cotterpin 20 extends through the apertures 16 and 18 of the bearings 15 and the shaft 17, respectively. and maintains the shaft 17 against axial or rotary displacement in the desired adjusted position.

The shaft 17 is also provided with a longitudinally extending slot 21 in which is. fixed. the end of a spiral brush'spring 22. The other end of the spring; 22 extends over and exerts a yieldable downward pressure against the brush 3. A flexible spring shunt 23 is preferably riveted to the spring 22, as indicated at 24, and which exterids downwardly and is soldered or otherwise suitably lined in an aperture 25 in the bottom 13 of the frame 1.

As illustrated in Figs. 3 and 4 of the drawinns, the apertures 18 in the shaft 17 are dis posed at intervals, those at the one end of the shaft 1.. being staggered with re spect to the similar apertures at the other end thereof.

By this arrangemen the shaft 17 may occupy double the number of rotary positions, without weakening the shaft than it the apertures 18 were in alinement.

i-he same results may be obtained by utilizing a plurality of apertures in one bearing element only, and by reversing the position of the shaft 17.

What I claim as my invention is:

1. A shaft mounting comprising a bearing element having a recess therein, a shaft mounted on said bearing and. provided with a plurality oi? apertures arranged in different planes, the apertures disposed in one plane beingstaggered with respect to those of the other, and means disposed in said bearing recess for engagement with the apertures in said shaft for maintaining the same in adjusted position.

A shaft mounting comprising a bearing element having a recess therein, a shaft mounted on said bearing and provided with a plurality of apertures arranged in parallel planes, the apertures disposed in one plane being staggered with respect to those of the other, and m ans disposed in said bearing recess for engagement with the apertures in said shaft for maintaining the same in adjusted position.

A shaft mounting comprising a hearing element having'a recess therein, a shaft mounted on said bearing and provided with a plurality oi apertures disposed in differ ent planes, the apertures in one plane being disposed out oi alinement with respect to those of the other plane, and means disposed in said bearing recess for engagement with the apertures in said shaft for niaintaininethe same in adjusted. position.

4. A shaft mounting comprising a bearing element, having a recess therein, a shaft mounted on said bearing element and provided with a plurality 01 groups oi radially intersecting apertures, the apertures disposed in one plane being staggered with respect to those oi the other, and means disposed in said bearing recess for engagement with the apertures in said shaft for maintaining the same in adjusted position.

5. A brush-holder comprising a frame, a brush carried by said frame, bearing members secured to said frame, a plurality of apertures in said bearing members, a spring support mounted in said bearings, a spring carried by said support for engagement with said brush, a plurality of recesses in said support arranged in different planes and in staggered relation with each other and adapted to be caused to register with the openings in said bearings, and means disposed within said apertures and IBLGSSBS :ior maintaining said support in an adjusted position.

In testimony whereof I have hereunto subscribed my name this 7th day of September, 1920.

JOHN S. DEAN. 

